If you've already got solar panels—or you're thinking about installing them—there's one question that can dramatically change your return on investment: What happens to the energy you don't use?
Without battery storage, excess solar energy gets exported back to the grid. You might earn a few pence per kWh through the Smart Export Guarantee, but you're essentially giving away free electricity and then buying it back at full price in the evening.
That's where battery storage changes everything.
The Problem with Solar Alone
Solar panels generate most of their power during the middle of the day. But when are you actually at home using electricity? Typically in the morning before work and in the evening when you return.
This mismatch means a typical household without storage might only use 30-40% of the solar energy they generate. The rest goes to the grid for a fraction of what you'd pay to buy it back.
How Battery Storage Transforms Your Savings
A home battery system stores your excess daytime generation for use when you need it. This simple change can boost your self-consumption from 40% to 70-80% or even higher.
Here's what that looks like in practice:
| Without Battery | With Battery | |----------------|--------------| | Use 40% of solar | Use 75%+ of solar | | Export at 4-5p/kWh | Store for evening use | | Buy back at 24p+/kWh | Avoid peak rates |
Over a year, this can translate to hundreds of pounds in additional savings.
Beyond Savings: Energy Security
Battery storage isn't just about money. It also provides:
- Backup power during outages - Keep your lights, fridge, and internet running when the grid goes down
- Protection from price spikes - As energy prices fluctuate, your stored solar keeps you insulated
- Smart tariff optimisation - Charge from the grid during cheap overnight rates, use stored power during expensive peak times
Choosing the Right Battery
Not all batteries are created equal. At Thermohome Solar, we work with leading brands that offer:
- 10+ year warranties with 6,000+ cycle guarantees
- Smart monitoring via smartphone apps
- Seamless integration with your existing or new solar system
Our most popular option is the 10kWh Home Battery System, which provides enough storage for most households to get through the evening and night on stored solar power.
Is Battery Storage Right for You?
Battery storage makes the most sense if:
- You have solar panels (or plan to install them)
- You're often out during the day when solar is generating
- You want protection against power cuts
- You're on a time-of-use energy tariff
Even without solar, batteries can save money by storing cheap overnight electricity for daytime use.
Take the Next Step
Curious about how much you could save with battery storage? Get a personalised quote that shows exactly what a system would cost and how quickly it would pay for itself.
Already have solar and want to add storage? We specialise in retrofitting batteries to existing systems. Our AC-coupled solutions work with almost any setup.